Page 1

PRECAST VOLUME Seven ISSUE 1 • 2013

the cma – QUALITY CAST IN CONCRETE

• A push for wider precast concrete usage • PPC – a true South African success story • CBP used extensively in Klapmuts


contents

1

precast contents message from the executive director 2 calling for new members

NEWS

22 armorflex lining protects embankments at silica mine 23 chryso products ideal for precast concrete wind turbines 25 lafarge’s cem ii aimed at precast concrete producers

3 sika sets up new

27 retaining walls offer varied

concrete laboratory

form and function

3 cma appoints new executive director

PRECAST VOLUME SEVEN ISSUE 1 • 2013

ON THE COVER

A cross-sectional view of the Isibonelo Colliery bunker under construction showing cast in-situ vertical columns, sloping precast concrete beams, precast panelling, and a cast insitu bunker floor, approximately one metre thick. See page seven for details of this case study which illustrates the advantages and flexibility of hybrid concrete technology. THE CMA – QUALITY CAST IN CONCRETE

4 BRIAN shackel – an obituary 4 sephaku cement builds integrated clinker/cement plant

• A push for wider precast concrete usage

• PPC – a true South African success story • CBP used extensively in Klapmuts

5

C&CI to close

5 afrisam regrets c&ci closure

ARTICLES 7 engineers push for wider precast concrete usage

Precast is the official journal of the Concrete Manufacturers Association (CMA) 16 Horn Street, Kempton Park, 1620 PostNet Suite 8612, Private Bag X32, Kempton Park, 1620 Tel: +27 11 805 6742, Fax: +27 86 524 9216 E-mail: admin@cma.org.za, Website: www.cma.org.za

10 ppc: a true south african

Publishers

success story

Isikhova Publishing & Communications

16 concrete block paving and

PO Box 651793, Benmore, 2010, South Africa Tel: +27 11 883 4627, Fax: +27 11 883 4627 Website: www.isikhova.co.za

precast concrete used extensively

in klapmuts housing project

Publisher: Andrew Meyer Tel: +27 11 883 4627, Cell 082 456 5175 E-mail: andrewm@isikhova.co.za Editor: David Beer

APPLICATIONS

Tel: +27 11 478 0239, Fax: +27 11 678 0254 E-mail: bigsky@ibi.co.za Advertising: Marni du Toit

18 safer scaffolding needed – MBA 18 afrisam re-engineers cement portfolio

Tel: +27 11 883 4627, Cell: 084 941 2469, E-mail: communications@isikhova.co.za Design, layout and production: Joanne Brook The views and statements expressed in this publication are not necessarily those of the editor or the publishers and neither he/

21 chatsworth precast concrete pavers going strong

48 years on

publishers nor the CMA accept responsibility for them. No person connected with the publication of this journal will be liable for any loss or damage sustained as a result of action following any statements or opinions expressed herein.

PRECAST VOLUME 7 • ISSUE 1 • 2013


2

MESSAGE FROM THE EXECUTIVE DIRECTOR

CALLING FOR NEW MEMBERS • A quality assurance system is in place

Material published by an association on

• Occupational, health and safety (OHS)

the other hand comes across as being

authoritati ve, application-dri ven and

procedures are in use

• Technical and engineering competence • Financial stability • Environmental compliance.

therefore influential. “Moreover, the CMA is the voice of the precast concrete industry. We are known to and engage with national and local

CMA Executive Director Wally Armstrong.

Benefits of CMA membership

governments in lobbying for the greater

• Being part of an association brand

use of precast concrete.

which is widely recognised and respected

“O u r s e m i n a r s, w h i c h a r e o f t e n

f or setting and maintaining best-

presented by overseas experts, are highly

practice standards

regarded by construction professionals

• Access to industry-specific statistical

and local authorities. The focus is on

information

providing practical and technical advice

• Posting CMA logo on company stationery,

which can be readily applied.”

website, packaging and products

A nother bene f it o f CM A member -

The Concrete Manufacturers Association

• Participation in the prestigious Awards

ship is the promotion of high-quality

(CMA) has broadened its membership base.

precast concrete in the technical press.

Unlike in the past when membership was

• Listing on the CMA website

The CMA runs a very successful public

dependent on certain product categories,

• Inclusion on the CMA mailing list

relations programme on precast concrete

membership is now open to any precast

• Membership discounts on seminars and

and its application, enjoying widespread

manufacturer providing certain conditions

editorial coverage across most of the

are met.

• Participation in setting national stand-

country’s construction-related media.

Moreover, it publishes its own magazine,

C M A e x e c u t i v e d i r e c t o r, W a l l y

for Excellence competition

educational courses ards for the industry

Armstrong, says the CMA promotes the

• Access to best-product design and

Precast, which is exclusively devoted to

widespread use of precast concrete and

precast concrete.

lobbies for best-practice standards in its

• Access to a pool of experts

manufacture and application.

• Access to technical literature

pursued by us than individual companies,”

• Opportunities to feature innovative

concludes Armstrong.

“We collaborate with the South African

manufacturing processes

“Again, these activities are more easily

Bur e au o f S t andar ds in in tr o ducing

pr ecast concr ete pr ojec ts in the

and revising industry standards, stage

CMA’s magazine, Precast

seminars, and publish technical literature

• Client referrals

of one’s pr of essional colleagues and

on precast concrete applications. Over

• Networking opportunities

the exchange of ideas. Participation in

the past 10 years we have been active

• Participation in and product displays

our prestigious Awards for Excellence

in promoting skills development and job

at exhibitions.

competition, held every second year, is

creation, and our producer members have

Like the SABS mark, the CMA logo is

yet another.

introduced several innovative precast

a widely recognised and respected brand,

The CMA has done much to grow the

concr e te pr oduc ts w hich ha v e been

a badge of quality if you will, and many

pr ecast concr ete industr y since our

used to enhance quality-of-life across all

construction professionals in the private

inception 40 years ago. We also know that

spectrums of society.”

and government sectors insist on CMA

the future potential for growth is huge.

members’ products.

We intend unlocking this potential over

Armstrong says that for CMA member-

Other benefits of CMA membership include access to the technical expertise

the coming years and we hope you’ll join

ship purposes, precast concrete is defined

“O n e b en e f i t o f asso cia ti ons like

as a concrete product cast in a re-usable

the CMA is that we are able to pro-

mould or form, cured in a controlled

mote precast concrete far more effec-

For f ur ther inf ormation contact

environment, transported to site and

ti v e l y th an in di v i du als th em s e l v e s,”

Pam Zukor on (011) 805-6742 or admin@

lifted into position.

comments Armstrong.

cma.org.za. P

Membership is granted on the basis of

handbooks could be and sometimes are

the following:

published by individual companies. The

• Production takes place in a purpose-

disadvantage is that company literature

is generally regarded as a hard sell.

“For example, technical manuals and

built manufacturing facility

PRECAST VOLUME 7 • ISSUE 1 • 2013

in this process.


NEWS

3

SIKA SETS UP NEW CONCRETE LABORATORY Sika has opened a concrete laboratory in

water-cementitious binder contents,

Gauteng, offering high-quality technical

while maintaining concrete workability and

support in the optimisation of concrete

strength development.

mixes f or semi-dry pavers, wet-cast

Fully functional, with brand-new equip-

precasters, RMC (ready mix concrete)

ment and skilled technologists on hand,

producers, and for testing shotcrete

Sika’s concrete lab is ready for business.

materials used in tunnelling and mining.

This additional laboratory means that

Mixes can be designed and tested

tests can be conducted more efficiently

for maximum per formance at the

and customer s ar e o f f er ed a v alue-

laboratory. Sika admixtures can reduce

added service.

Sika’s new laboratory in Gauteng.

CMA APPOINTS NEW EXECUTIVE DIRECTOR Wally Armstrong has been appointed

as vice president until 2005, and was then

last 10 as marketing director – where,

executive director of the Concrete Manu-

appointed president of the Association.

among other notable construction-related

facturers Association (CMA). Armstrong

Armstrong also heads a marketing

achievements, he established a separate

has had a long and mutually beneficial

consultancy, AMA Marketing, which he

division for precast concrete poles and

relationship with the CMA. He co-founded

established in 2005. During the previous

introduced an entrepreneurship training

the P.I.P.E.S. Division in 2001, which he led

21 year s he worked f or Rocla - the

academy for the previously disadvantaged.

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4

NEWS

Brian Shackel – an obituary World renowned paving engineer, Australia’s

Part of his local research involved

Dr Brian Shackel, lost his battle with cancer

ex tensi v e testing on the shape and

on 18 November last year. He was known

thickness of local concrete paving blocks,

Brian taught pavement engineering

to and well liked by many in the precast

on the quality of bedding sand and how it

at the University of New South Wales at

concrete paving industry, especially to

affected paving installations. His work had

both undergraduate and post-graduate

members of the South African Concrete

a profoundly positive impact

levels f or more than 35

Manufacturers Association (CMA ), to

on the local paving industry,

years and was well known

whom he was both friend and mentor.

transforming it into a world

to international audiences,

leader in Concrete Block

having travelled and

Paving (CBP) technology.

lectured extensively in 24

A former professor of the University of New South Wales, Brian visited this country

Olympics won him a further award from the CIA in 2001.

regularly, his last stopover was in 2010

Brian published three

countries, which besides

when he ran a series of seminars on perme-

books on CBP and his work

South Africa, included the

able concrete block paving (PCBP) systems.

on paving design software,

USA, Canada and many

However, his ties with South Africa

L ock Pa v e, won him an

European destinations.

stretch back to the early eighties when,

Award for Excellence from

In addition to his academic

over two years, he conducted accelerated

the Concrete Institute of

pursuits, Brian also worked

testing of local roads and airport paving

Australia (CI A ). He also

in Pretoria for the CSIR’s National Insti-

co-authored PermPave, custom-made

tute for Transport and Road Research.

software for South African permeable

on many projects worldwide. He was

There was no official paving block standard

paving installations.

especially celebrated for his contribution

Dr Brian Shackel

as a consultant for asphalt,

block paving and rigid concrete pavements

back then and Brian’s research provided

He published more than 100 research

to heavy duty pavements, including those

the basis for subsequent SABS stand-

papers dealing with geomechanics and

for ports, container handling facilities and

ards in the manufacture and application of

pavement engineering, and his involvement

airports, and he was a recognised authority

paving blocks.

as paving coordinator for the Sydney

on ecological and permeable paving systems.

SEPHAKU CEMENT BUILDS INTEGRATED CLINKER/ CEMENT PLANT IN NORTH WEST PROVINCE Sephaku Cement is erecting an integrated

will produce 6 000 tons of clinker a day and

most of the construction components on

clinker and cement plant, Aganang, in North

1.2 million tons of cement a year. It will also

site included:

West Province. At a cost of R2,8 billion, it

compete head-on with other major cement

• An eight-week site preparation in which

is also one of the country’s largest capital

producers and will go to market with the

some some 128 000m 3 of cut and

projects currently under construction.

same grades.

155 000m3 of fill were processed

Aganang will utilise the limestone

Heinrich de Beer, Sephaku Cement

deposits of the Stiglingspan and Verdwaal

engineering project manager, comments

farms situated some seven kilometres

that with a storage volume of 56 000 tons,

• T he 15m (height) x 8m (diameter)

south west of Ltoseng and 25km west of

its clinker silo will be one of the largest of

concrete cone in the raw-meal silo

Lichtenburg. When commissioned at the

its kind in South Africa.

was completed in just 10 days

end of the year, the state-of-the-art plant

“Its kiln too will be the country’s largest and longest burning. The plant’s raw meal

The Sephaku cement/clinker plant under construction.

PRECAST VOLUME 7 • ISSUE 1 • 2013

• Slip-forming at 4m lifts every 24 hours, a rate exceeding the industry average

• Brick-laying teams laid between 1 000

and 1 200 bricks per layer, per day.

silo capacity will be 20 000 tons and its

Sephaku Cement was founded in 2006

finished-cement storage capacity will be

and Aganang is the first clinker factory to

approximately 22 000 tons. Some 13 000

be built in South Africa since 1934. The

tons of rebar was used in its construction

company is a 64% owned subsidiary of

and standar dised shu t ter sizes and

Dangote Cement Plc and is an associate

uniform foundations have led to impressive

of JSE-listed Sephaku Holdings limited.

construction speeds.”

Dangote has invested more than R1 billion

De Beer said that some of the

in the venture, representing the largest

efficiencies achieved through using small

investment in a South African enterprise

structured teams as well as manufacturing

by an African company to date.


NEWS

5

C&CI to close After 75 years of serving the construction

T he pr ocess r equir ed to gi ve e f f ect

and the services normally provided by the

industry in South Africa, the Cement &

to this decision will commence with

Institute will be severely curtailed.

Concrete Institute will be closing down.

immediate effect (27 Feb 2013) and is

More detailed announcements will be

This decision was reluctantly taken by

expected to take two to three months

made in this regard as soon as information

the C&CI board following the resignation

to complete in its entirety. During this

is available.For further information, contact

of the Institute’s main funding members.

period the closure will be the main focus

Bryan Perrie, C&CI MD on Tel 011 315 0300.

Afrisam regrets C&CI closure It is with regret that AfriSam confirms that

from the Cement and Concrete Institute.

products to suit particular specifications

the Cement and Concrete Institute will be

As part of the closure process, AfriSam

and applications. AfriSam’s Centre of

closing down. This follows the withdrawal

will participate in the steering committee

Product Excellence supports customers by

of funding from some of the key funding

meetings and will play an active role to

providing scientific and technical expertise

members. AfriSam believes in the value that

ensure that this process is conducted in a

as well as innovative technical solutions.

the Cement and Concrete Institute offered

professional, fair and responsible manner.

AfriSam would like to use this opportunity

the construction industry and explored

AfriSam is regarded as one of the

to thank the Cement and Concrete Institute

various other options in an effort to sustain

preferred technical centres in the country

for the valuable role it has played in promoting

this industry body. Unfortunately, no

and its product development team in

the interest and general advancement of the

solution could be found. As a result, AfriSam

Roodepoort, Johannesburg work closely

cement and concrete industries as a whole

had no choice but to tender its resignation

with customers to develop and test

in southern Africa over the past 75 years.

PAVING DOESN’T HAVE TO BE BRICKS.

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Natural Beauty Yet Engineered Quality


ARTICLE

engineers PUSH FOR WIDER PRECAST CONCRETE USAGE A special task group comprising consult ing engineers, specialist precast concrete contractors, main cont ractors, academ ics and an architect, has been formed to promote the greater use of precast concrete construction in South Africa.

“Not that long ago it was far more widely

7

or precast in a factory environment. All of these techniques can be combined in a single project. Moreover, individual c oncr e t e elemen t s c an b e de signe d and built combining in-situ and precast concrete in what is known as hybrid concrete,” Theodosiou explains. “Hybrid concrete takes full advantage of the inherent qualities of both forms of casting. The accuracy, speed and highquality finish of precast components can be combined with the economy and flexibility of cast in-situ concrete.

used. For example, half the Sandton City

“For instance, hybrid concrete con-

retail, commercial and hotel development

struction simplifies the more complex

in Gauteng, as well as buildings in Sand-

connection details sometimes associated

ton’s business precinct were built using

w i th n o r m al p r e c as t c on cr e t e c on -

precast concrete elements; so was much

struction. It also allows engineers to

of Sun City.”

design structures or elements with full

Theodosiou believes structural precast

continuity, similar to that found in in-situ

concrete contractors could do much more

construction, as opposed to pin-joint

to market their products and expertise

designs which are sometimes associated

One of its members, structural engineer,

among structural engineers and other

with precast concrete.

G ar y T heodosiou, say s constr uc ting

professionals.

“H y br id concr e te constr uc tion

with precast concrete elements offers

“Property developers are missing out on

p r o du c e s simp l er m o r e c omp e ti ti v e

several advantages. These include: quicker

the superior design opportunities offered

structures. The client is given better value

construction owing to reduced propping;

by precast concrete, particularly in the

and the contractor benefits from increased

improved and consistent quality thanks to

use of columns, beams, and staircases.

off-site component manufacture, safer

the controlled environment that factory-

Professionals who tend to favour structural

and faster construction and consistent

based production provides; and enforced

steel as a faster construction technique

performance,” he adds.

coor dina tion and teamwor k because

are probably unaware of the quick lead

Theodosiou says precast concrete

construction, layout and connection details

times and the huge amount of flexibility

construction addresses all the important

have to be planned well in advance.

offered by precast concrete.

requirements for sustainable concrete

“Despite these benefits precast con-

“As a building material, concrete can

crete falls considerably short of its full po-

either be cast in-situ, precast on site, as

tential in this country,” says Theodosiou.

in the case of tilt-up and stack-casting,

An external lateral view of the Isibonelo Colliery bunker, showing the vertical cast in-situ columns, precast concrete sloping beams and the precast panelling.

PRECAST VOLUME 7 • ISSUE 1 • 2013


8

ARTICLE

structures, including durability, quality, and speed of construction, appropriate finishes and cost-effectiveness. “Concrete, both in-situ and precast, is one of the world’s most durable materials. Well-designed, well-produced concrete offers exceptional performance and long life, and is a first line of defence against most forms of erosion.” Precast production facilities can either be situated in an established factory or on site. Because precast concrete is produced in a controlled environment (typically referred to as a precast yard), it is possible to monitor all stages of production including curing, compaction, the quality and depth of cover concrete, and strength requirements. Precast concrete is generally cast at

A cross-sectional view of the Isibonelo Colliery bunker under construction, showing cast in-situ vertical columns, sloping precast concrete beams, precast panelling, and a cast in-situ bunker floor, approximately one metre thick.

ground level which assists with safety and productivity and offers greater control

Case study: Isibonelo Coal Bunker

caused by the loading and off-loading of coal

of quality and workmanship, unlike the

An 8 000 ton coal bunker at Anglo Coal’s

in the bunker could be resisted.

exposed and awkward access presented

Isibonelo Colliery illustrates the advantages

T he panels wer e cast horizontally

by in-situ casting. In addition, the precast

and flexibility of hybrid concrete technology.

under ideal conditions and after seven

route often results in better durability with

Designed by Lyonell Fliss & Associates and

years of continual usage, the concrete

consequent savings in maintenance costs,

constructed by Murray and Roberts in

shows no visible sign of deterioration. By

time, materials and energy.

2005, the foundations and columns were

contrast, in-situ constructed coal bunkers

constructed with in-situ concrete.

usually require 50mm thick steel plates

Moreover, the forms used in precast concrete production may be re-used

The horizontal bottom slab was cast in-

or rail liners for added wear-protection.

hundreds if not thousands of times be-

situ on precast beams which in turn rested

This is because in-situ casting in sloping

fore being replaced. This ensures that

on in-situ columns. The remainder of the

formwork often results in honeycombing

the costs of formwork per unit are lower

bunker, including inclined and vertical wall

and inadequate compaction, leaving a

than that of in-situ construction, where

panelling, as well as sloping beams, were

30MPa concrete vulnerable to the abrasive

formwork can cost between 35 - 60 % of

all constructed with precast concrete

nature of sliding coal.

the cast elements.

elements and lifted into position by crane.

Controlling quality standards is much

The use of both in-situ and precast

easier in a precast yard and concrete

concrete meant that connecting the

elements which don’t meet the quality

various concrete elements to each other

requirements can be rejected before instal-

was considerably simpler.

lation. It is far more difficult to assess and

A considerable amount of time was

maintain quality in an in-situ constructed

saved by casting the precast elements in

bunker, where climbers are required to

concert with the excavation work and the

assess and repair poor quality concrete

in-situ construction of the foundations,

in awkward dangerous positions/heights.

columns and the horizontal floor-slab. This

In short the advantages of constructing

meant that the precast elements were

the concrete bunker walls and floor in

ready to be lifted into position soon after

precast concrete as opposed to in-situ

the in-situ concrete columns had been

concrete are as follows:

completed.

• Cost savings on steel plate or rail liners

A no ther bene f i t o f using pr ecast

A precast panel is lifted into position prior to installation on the sloping wall of Isibonelo Colliery.

PRECAST VOLUME 7 • ISSUE 1 • 2013

• Better concrete durability

concrete for the bunker was the quality and

• Easier jointing

finish of the concrete panels used to build

• Speed of construction

the inclined and vertical bunker walls. A 60

• Cost savings due to less labour and

MPa concrete with a surface hardener was

specified to produce a smooth, durable and

• Superior quality resulting in less

hard-wearing surface so that the abrasion

maintenance.

material required P


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10

ARTICLE

De Hoek Plant.

PPC: A true South African success story PPC Ltd is the leading supplier of cement in southern Africa. Based in South Africa, Botswana and Zimbabwe, the PPC’s manufacturing facilities and milling depots have the capacity to produce eight million tons of cement per annum. The group also produces aggregates, metallurgical-grade lime, burnt dolomite and limestone. In addition to serving its domestic markets, cement and lime are also exported to other African countries.

Limited, and went on to declare its first dividend, a trend which it still follows to this day. PPC’s expansion into the south PPC continued to grow, acquiring Northern Lime Company (PPC Lime) in the then Northern Transvaal in 1907 and a Slurry f ac tor y in 1916, in the Nor th West

PPC Ltd’s roots date back 121 years

Where it all started

Province. In 1921, PPC established Cape

to 1892, when it established South

Established as De Eerste Cement Fabrieken

Portland Cement and built a factory at De

Africa’s first cement plant. In 2010, PPC

Beperkt in 1892, PPC has tracked the

Hoek, near Piketberg in the Western Cape.

Ltd celebrated its centenary year on the

growth and development of South Africa,

Johannesburg Stock Exchange, joining an

producing the cement used in many of the

extremely small and elite group of listed

country’s iconic landmarks and construc-

centenarians, not only in South Africa but

tion projects, including the Union Buildings,

worldwide.

Gariep Dam, Van Staden’s River Bridge,

To r emain the mar ke t leader, the

Gautrain, Medupi Power Station, the new

cement giant has continuously improved its

Cape Town Stadium in Green Point and much

process technology to meet the country’s

of southern Africa’s infrastructure.

cement needs and to enhance productivity and efficiency at its factories.

PRECAST VOLUME 7 • ISSUE 1 • 2013

In 1908, the company changed its name to the Pretoria Portland Cement Company

JSE - Hollard Street.


ARTICLE

11

This quarry, together with the Laezonia

One of Gordhan’s focus areas is to

Quarry in Muldersdrift and the Kqale Quarry

engage with Government, contractors and

in Botswana, makes up PPC Aggregates.

banks on the Government’s long-stalled

PPC was included in the FTSE/JSE Top

infrastructure programme. PPC will also

40 Companies Index in 2003 and in 2006,

consider participating in private-public

it joined the JSE Socially Responsible

partnerships (PPPs).

Investment Index.

“We have a capacity that the government

Since unbundling from Barloworld in

may not always have. I want to engage more

2007, PPC concluded a R3,9 billion broad-

effectively with government,” said Gordhan.

based black economic empowerment transactions in 2008 and 2012, commissioned a

The modernisation of PPC

R1,4 billion clinker plant in Dwaalboom and

PPC has embarked on a modernisation

completed the R700 million mining facility

campaign which will ensur e that the

at its Hercules plant.

company has competitive, energy efficient plants which will comply with future changes

Rhodes Memorial.

PPC’s expansion into the rest of Africa

in South African environmental legislation.

PPC is a truly African success story –

Part of this process involves upgrading The

a focused business that reflects the

Riebeeck and De Hoek cement factories,

strengths of its people, products and

which when completed, will be able to meet

services. The group’s expansion into the

the Western Cape’s cement demand for the

rest of Africa is based on a business model

next three decades.

of sustainability and brand dominance in its chosen markets. The group aims

Technology upgrades at PPC plants

to grow into a leading emerging-market

A new si x-st age pr ehe a ter k iln was

The company entered the Eastern Province

business, starting in sub-Saharan Africa.

commissioned in 2008 at PPC’s Dwaalboom

in 1927 with the establishment of the

Maintaining its performance and industry-

factory, making it one of the most efficient

Eastern Province Cement Company, and

leadership in its historical markets is

clinker production kilns in South Africa.

the construction of a cement factory on

crucial to this strategy.

the outskirts of Port Elizabeth.

In 2010, PPC commissioned a new

PPC began making in-roads into the

vertical roller mill for cement grinding at its

Always at the forefront of innovation,

rest of Africa via acquisitions in 2012. This

Hercules factory that significantly reduces

PPC converted its slurry factory from a

included a 27% stake in Ethiopia’s Habesha

milling energy costs.

wet process to the more efficient and

Cement Share Company for R100 million

Sinc e 20 03, PP C has b e en c o -

cost-effective dry-mix system in 1958 and

and a 51% stake in Rwanda’s Cimerwa for

pr ocessing al ter na ti v e f uels, and is

a second Western Cape cement factory was

R630 million. And in February this year,

commissioned at Riebeeck in 1960.

PPC announced its intention to invest in

PPC became a subsidiary of the Barlow

a new one-million-ton-per-annum cement

Rand Group in 1977.

plant in Harare.

PPC in the new South Africa

Recent developments

After Nelson Mandela became the first

Last year, Pretoria Por tland Cement

democratically elected president of South

Company Limited changed its name to

Africa in 1994, PPC reached an agreement

PPC Ltd.

with the Botswana Development Corpora-

The name change is premised on a

tion to construct a cement blending plant

streamlined corporate structure with

and depot in Gaborone, which was commis-

discrete South African and international

sioned two years later.

operating entities. All South African

In the same year, PPC launched the first branded general-purpose cement,

operations will be divisionalised under a new operating company.

SureBuild, to the South African market. It

In 2013, PPC welcomed Ketso Gordhan

also introduced Botcem into the Botswana

as its new chief executive officer. Gordhan

market. In 2001, PPC acquired ownership

succeeds Paul Stuiver, who held the

of Portland Holdings Limited, Zimbabwe’s

position of CEO since 2009. Ketso brings a

leading cement company.

wealth and blend of experience in business

PPC also purchased the Mooiplaas dolomite quarry on the outskirts of Pretoria.

and in government, as well as knowledge of various industries.

Eerste Fabrieken Beperkt’s certificate of registration.

PRECAST VOLUME 7 • ISSUE 1 • 2013


12

article

accelerating this activity by increasing the usage of renewable fuels. The completion of a tyre recycling process will allow the group to reduce coal consumption at many of its kilns. The company is also committed to the procurement of at least 10% of its electrical energy from renewable sources. Recently, the Depar tment of Energy awarded a 60 MW wind-energy allocation to the Grassridge project in the Eastern C ape. T his pr ojec t, which is on a PPC proper ty, is aligned to a private wind farm development that will produce renewable power exclusively for PPC. Hercules Plant.

PPC: leading the market The enhanced PPC Surebuild, Unicem (Zimbabwe), Botcem

with better strength-

a 26% black ownership level within PPC

(Botswana) and Obras (Mo-

development properties.

South Africa. This achievement can be

zambique) products are all

Moreover, by adding more

attributed to the company’s commitment

extended or composite ce-

stone (aggregate) and sand,

to transformation and over eight senior

ments, engineered with lower

but the same amount of

black executives have been appointed

carbon footprints without

cement, 15% more concrete

with a special f ocus on black f emale

sacrificing performance. In

can be produced.

representation.

addition, the higher strength

In July 2012, PPC placed an additional

OPC and Surebuild require 15% less

PPC’s transformation

39.3m ordinary shares, equivalent to

cement for concrete production - thus

During the past couple of years, PPC

6.5% of the company’s increased share

lowering carbon footprints.

has progressed from a Level 7 Black

capital, under black ownership. The first

T hese recently improved products

Economic Empowerment (BEE) rating to

phase of the Broad Based Black Eco-

p r o v i d e c o n s t r u c t i o n p r o f e s si o n a l s

a Level 2 rating last year, when it reached

nomic Empowerment (BBBEE ) transaction for 15.3% was closed in 2008. The second phase will result in the increase of direct black ownership of the PPC Group to 20.8%. Of the additional shares being issued, 68% will be issued to employees of PPC’s South African businesses. Twenty seven percent will be issued to PPC’s existing strategic black partners (SBPs) and five percent to a newly created trust that will focus on black women in areas where the company operates. This transaction was structured for the benefit of those parties living in close proximity to the group’s businesses. Some 2 400 South African employees are participating and will own seven percent of the group. Setting the benchmark in

PPC’s expansion strategy.

PRECAST VOLUME 7 • ISSUE 1 • 2013

gender transformation The difference between a good company and


ARTICLE

13

a great one is its people. PPC recognises

group saw a 67% increase in its female

the broader industry. As a leader in this

the importance of attracting the country’s

employee ratio and a four-fold increase of

industry, and always at the forefront of

best to maintain its position as the leading

women in management roles. By the end of

innovation, the cement giant has actively

cement manufacturer in southern Africa.

last year, female employees represented

invested in technology to r educe air

The company believes emphatically that

20% of PPC’s total workforce.

emissions, minimise waste production,

by providing the opportunities, resources

PPC applies a learning-f or-gr ow th

r e c y cl e an d r e c o v er r a w m a t er ials,

and means, it enriches its employees and

principle across the group and has close

enhance energy efficiency and conserve

assists them in reaching their full potential.

to 10 academies and programmes in place

natural r esour ces while pr oducing a

To i n s t i l l f a i r t r e a t m e n t a c r o s s

– ranging from basic adult education and

reliable and affordable supply of building

gender, the cement manufacturer has

training, to graduate development and

materials to support the economies in

implemented various pr ocesses to

bursary initiatives for future engineers.

countries where it operates.

ensure that it attracts more females to

To attract f emales to the in-f ield

As a proudly African cement company,

this once male dominated industry. The

work, PPC provides a mining academy

PPC will continue to grow as a leading

company further aims to develop and

on a rock-breaking opencast quarrying

emerging-market business. The company

nurture its existing female employees’

qualif ication, which is r ated at NQF

currently operates in emerging markets,

skills and talent.

Level 3. Breaking old barriers in this

and all its adjoining territories are in

In 2011, the company launched the PPC

field is Norma Dyanti, based at PPC

emerging markets. Importantly, 70% of

Women’s Forum which aims to attract,

L im e A c r e s i n N o r t h e r n C a p e . S h e

the world’s cement is produced in these

nur ture and advance women’s talent

progressed from an operator support

markets. Emerging markets continually

to lead PPC. It is also a platform where

role to achieving a blasting certificate.

present new opportunities, higher growth

creativity and innovation is encouraged. Over the last decade, the number of female employees has expanded, and the

in populations, GDP and cement demand, PPC’s vision for the future

and deliver higher returns for producers

PPC’s focus extends beyond the group, to

of cement and related products.

P

EROSION PROTECTION SOLUTIONS

erosion protection paving

precast products concrete masonry drainage

kerbs

retaining walls

An engineered erosion solution that can withstand even the most severe climatic conditions. • Armorflex offers environmental protection • Labour intensive and cost effective • Complete erosion protection (even when placed under water) Tel: 0861266267 www.technicrete.co.za


Š All rights reserved


THE WORLD OF PRECAST CONCRETE CMA proudly presents phase one of the World of Precast Concrete which introduces the precast city. These maps will be made available to members and potential clients in print and electronic format. In the electronic version, one will be able to zoom in and click on various points which will be linked to members’ websites.

www.cma.org.za

For more information contact the CONCRETE MANUFACTURERS ASSOCIATION 16 Horn Street, Kempton Park, 1620 PostNet Suite 8612, Private Bag X32 Kempton Park,1620 Tel: +27 11 805 6742 Fax:+27 86 524 9216 E-mail: admin@cma.org.za


16

ARTICLE

A close up of one of the concrete block paved roads in Klapmuts.

CONCRETE BLOCK PAVING AND PRECAST USED EXTENSIVELY IN KLAPMUTS HOUS Very wet winters, a high water table and unstable sub-grade material (earth) has necessitated approximately half a 24 000m² road-building and access-course project in Klapmuts, Western Cape, to be surfaced with concrete block paving (CBP) because of its superior strength and stability properties. Asphalt was only used where the water table was deemed low enough and the sub-grade sufficiently stable by the main contractors, Power Construction.

some 11 000m² with CBP, 6 600m² of

The road-building project forms part of a

concrete block paving was deployed in the

turnkey housing contract which is being

sections where the sub-grade was unstable.

access course and 4 400m² of roads. Asphalt was only used where the subgrade was considered sufficiently stable. Steven Levey, senior quantity surveyor at Power Construction, said that the contract includes a 10-year latent defect clause and this was the main reason why

financed by the Department of Human

“CBP pr ov ides a long-term pav ing

Settlements. It was awarded to Power

solution unlike asphalt, which under these

Construction in a tender process by the

conditions, would most likely have begun

Stellenbosch Municipality, for whom the

cracking within five years. Moreover, CBP

project is being undertaken.

surfaces are aesthetically pleasing and

It involves the construction of 1 067 x

can easily be lifted and replaced as new,

40m² subsidy houses in two phases over

for example, for the installation of electric

five-years. Phase 1 is being undertaken

cables, which often takes place after the

in two portions of which Phase 1A sees

roads have been laid.”

the construction of 480 houses, due for

Power Construction’s contracts manager,

completion by the end of March this year.

Pietre Smit says that grey 60mm and

Designed by BKS Consulting Engineers

80mm 35MPa inter lock ing concr e te

and built by Seymour Paving, the road and access-course project involved surfacing

PRECAST VOLUME 7 • ISSUE 1 • 2013

A recently constructed concrete block paved road in Klapmuts.

paving blocks were used for the CBP. They were supplied by Concrete Manufacturers


ARTICLE

One of the precast concrete staircases being used in the construction of the double-storey units at Kalpmuts.

PRECAST CONCRETE SING PROJECT

17

Some of the hollow-core slabs which were used on the double-storey units at Klapmuts.

masonry; precast hollow-core slabs for

greater sense of community among the

second-storey flooring of the double-storey

lucky few who qualify for these houses.

units and precast staircases, supplied by

Another plus was the fact that that

Cape Concrete; and concrete roof tiles

much of the labour for the project was

supplied by CMA member, Eagle Roof Tiles.

drawn from the local community. Many

“Hollow-core slab flooring is ideal for

of them wer e unsk illed and r ecei ved

multi-storey structures, not only for

CE TA-accredited training from Power

Association (CMA) member, C.E.L. Paving.

subsidy housing, but for designer homes,

Construction,” concluded Armstrong.

“We laid the paving on a G4 base which

hotels, apartment and office buildings as

is superior to a sub-base and can easily

well. It’s a much faster and cleaner building

withstand the high water table. Moreover, it

process than in-situ flooring, and because

has good load-bearing capacity,” said Smit.

it’s produced in a factory environment,

Seymour Paving director, Jon Whiting,

offers high and consistent quality.

said the borders of both the access

“Similarly, precast staircases provide

courses and the roads were edged with

an e x c e ll e n t b uil ding s o lu ti o n . T h e y

double-cobble pavers (see photo), which

are much easier to install than their

were also supplied by C.E.L. Paving.

steel or timber equivalents and require

“It finishes off the project very neatly,” said Whiting,” and we have used the process extensively on other projects.”

no maintenance.” The largest precast component of the

One of the concrete block paved roads in Klapmuts which clearly shows the neat finish of double-cobble edging.

Klapmuts project was the masonry which

CMA executive director, Wally Arm-

comprised concrete blocks in three sizes

strong, says this Klapmuts subsidy housing

400mm x 200m x 190mm, 400mm x

project, which was NHBRC approved, is an

200mm x 140mm and 400mm x 200mm

excellent showcase for precast concrete.

x 90mm. Once built, the outer walls were

‘Not only was CBP chosen for the roads

plastered and painted and the inner-walls

because of its superior durability and all-

P

were bag-washed.

weather properties, but precast concrete

“Given the superior aesthetic pro-

formed the main building components in

perties of CBP and concrete roof tiles

the construction of the houses. These

has meant that the Klapmuts project is

included: precast building blocks supplied

visually appealing, and as such, is likely

by CMA member, Boland Concrete for the

to encourage pride-of-ownership and a

A concrete block paved road at Klapmuts under construction.

PRECAST VOLUME 7 • ISSUE 1 • 2013


18

applications

All materials used in scaffold construc-

safer SCAFFOLDing NEEDED – MBA

tion must be inspected for conformity with

A recent scaffolding accident, which left

design is prepared so that it can safely

the structure will be built must also be

one person dead and 19 injured after heavy

withstand the load it will hold as well as

inspected. Scaffold structures may only be

winds overturned the framework, has

vertical and horizontal wind pressures.

constructed by trained, competent scaffold

highlighted the need for strict adherence

Any scaffolding that does not fall into one

erectors under the direction of a supervisor.

to standards regarding correct scaffolding

of these categories must be designed by a

Supervisors must possess the necessary

design and construction. Deon Bester,

scaffold designer or professional engineer.

qualifications from an accredited training

required standards. The area on which

occupational health and safety manager

provider and approved by the South African

at the Master Builders Association (MBA)

Qualifications Authority (SAQA). They must

of the Western Cape, shares his expert

also comply with the legal construction

advice on how to prevent accidents like

regulations as well as those contained in

this from happening in future.

the SANS Code. Moreover, all scaffold erec-

The design and construction of any

tors must have undergone the requisite 18

steel tubular scaffold must comply with

months of classroom and practical training.

the South African National Standards

Once the structure has been built, it

( S A NS ) C o d e 10 0 8 5. T his c o n t ain s

must be inspected and declared fit for

requirements for design, maintenance,

use. No untrained people are allowed to

inspection, safety precautions and usage.

alter or remove items from existing safe-

To erect scaffolding that conforms to the

scaffold structures as the removal of

standards contained within the Code,

one component would render the entire

there are a few aspects which need to be

scaffold structure unsafe.

taken into consideration. These include

If the scaf folding is enclosed with

the condition of the surface on which

sheeting, shade netting or advertising

the scaffold is to be built, and the loads,

banners, this must be investigated and

weather and the wind pressures to which

approved before use since it could affect

it could be subjected.

wind loading. The scaffolding needs to be checked once a week, especially after

Scaffolding is divided into four specific

inclement weather or alterations, with

categories, based on the weight it is able to bear safely. The type of scaffolding required must be determined before a

Strict adherence to standards regarding correct scaffolding design and construction is essential for ensuring the safety of contractor employees and the public.

the details of these inspections recorded in a register.

AFRISAM RE-ENGINEERS CEMENT PORTFOLIO AfriSam has revised its entire product

said Neser. “We are particularly proud

All Purpose Cement is that it achieves

portfolio.

to have achieved the ‘R’ rating while

the equivalent seven day strength re-

A f r i S a m’s c o mm e r c i a l e x e c u t i v e,

retaining an ex tremely low carbon

quired from the old 32.5N class within

Grant Neser, says: “The revised product

footprint. We’ve effectively introduced

only 2 days.

line delivers ef fective, fit-for-purpose

technological advances that have boosted

Neser says AfriSam’s popular Eco

cements. This is the first time the company

the strength, durability, workability and

Building Cement has a carbon footprint

has introduced product improvements

performance associated with advanced

less than half the world average f or

across its full range on such a broad scale

composite cements, without sacrificing

cement and has now changed from the

- and more is to come.

sustainability.

32.5N to the 42.5N strength class.

“Over the years, AfriSam has made

“By moving to the ‘R’ class, we are now

“This is a true construction grade

a considerable investment in the

able to offer 15% more concrete which is

cement,” say s Neser, “which means

de v elopment o f ad v anced composi te

becoming the norm for leading brands.”

that it can be used in both construction

cements. The new line-up reflects our

Engineered as an all-round general

and general building applications. It has

commitment to delivering superior value

purpose cement for concrete, mortar,

the ability to produce high-performance

and to environmental responsibility.

plaster and screed applications, AfriSam’s

concrete with strengths as high as 60

“Our pr emium br and, A ll P ur pose

All Purpose Cement is spearheading the

MPa easily achieved. It is ideally positioned

Cement, has now been upgraded from

launch of its revised product portfolio.

for use in concrete, mortar and plaster

the 32.5N to the 32.5R strength class,”

An important feature of the new 32.5R

applications for Green buildings.”

PRECAST VOLUME 7 • ISSUE 1 • 2013


OUR DOOR

IS OPEN BECOME PART OF THE FUTURE

WE INVITE ALL PRECAST CONCRETE MANUFACTURERS TO JOIN US *

www.cma.org.za

* TERMS AND CONDITIONS APPLY

CONCRETE MANUFACTURERS ASSOCIATION 16 Horn Street, Kempton Park, 1620 PostNet Suite 8612, Private Bag X32, Kempton Park, 1620 Tel +27 11 805 6742 • Fax +27 86 524 9216 • E-mail: admin@cma.org.za


APPLICATIONS

21

A paved road in Chatsworth.

CHATSWORTH PRECAST CONCRETE PAVERS GOING STRONG 48 YEARS ON C

These precast Concrete Block Pavers

M rights to manufacture the S.F. block paver

(CBP) were laid 48 years ago in

south of the equator.

Y

Chatsworth, Durban and according to

Shortly after Hall’s return, the annual

Concrete Manufacturers Association

brick road tender was issued by Durban

(CMA) president, Taco Voogt, they look

MY Municipality, and Hall placed a provisional

good for at least another half century.

CY order for an S.F. Roadstone CBP machine.

When they reach the 50 year mark they will

He then tendered against a clay brick CMY

have provided twice the length of service

manufacturer and won the paving award

expected from a good tarmac road.

for Chatsworth.

CM

K

What is more, the roads have been

This led to the installation of a CBP plant

essentially maintenance-free, unlike their

in Chatsworth by German fitters, and the

asphalt equivalent installed in Chatsworth

production of S .F. pavers to a minimum

around the same time. The little upkeep

strength of 5 000psi (±35MPa) – the

that has taken place was not the result

prevailing German standard - commenced.

of surface failure, but was due to the

Strict control of aggregate grading and mix

installation and repair of water pipes and

design, personally handled by Hall, meant

electric cables which run under the roads.

that the quality and crushing strength of

Moreover, pockets of heaving clay were

the pavers was very high. On completion of

subsequently encountered, a condition

the contract in 1967 the machinery was

in which tarmac cracks and breaks up. In

relocated to Hume Pipe Co in Pinetown.

the case of Chatsworth’s CBP roads, the

Voogt adds that good bedding material

pavers were simply lifted and relaid after

and sub-base engineering also played a

the clay had been replaced with sabunga

substantial role.

(compacted stone and sand).

“This project proves quite emphatically

The project was initiated and con-

what the CMA has been promoting for the

trolled by Derek Hall, Pr.Eng. who says it

past 30 years, namely that CBP is an ideal

was the first of its kind in Africa south of

surface material for suburban and town-

the equator.

ship roads. Besides offering exceptional

Der ek discover ed concr ete block

maintenance-free performance, CBP is

paving technology during a business trip

also labour intensive, creates employment

to Germany in 1964 when he was general

and skills the unemployed, and therefore

manager of Hume Rhodesia Co. He visited

is ideally suited to the Government’s Ex-

the headquarters of the S.F.Roadstone

panded Public Works Programme (EPWP),”

Co in Bremen and negotiated the African

advises Voogt.

PRECAST VOLUME 7 • ISSUE 1 • 2013


22

APPLICATIONS

ARMORFLEX LINING PROTECTS EMBANKMENTS AT SILICA MINE Technicrete has supplied Ansaki Construc-

cabling to from a mattress-like finish which

tion with its Armorflex 180 erosion control

can withstand high-water velocities and

system to line embankments at Silica Mine

wave attack.

in Polokwane.

Mats in alternative sizes and weights

Ansaki’s Adriaan Willems said “We

can be produced for special applications.

required a lining that offered superior

Armorflex can be installed around rocks and

anti-erosion properties, facilitated easy

boulders and is not damaged by the constant

water flows and maintained the integrity

influx of debris into a channel or onto an

of the subgrade.

embankment. The blocks’ tapered design

“A r m o r f l e x 18 0 i s s p e c i f i c a l l y

reduces stress, provides mat flexibility and

designed for this kind of project. The

prevents slippage. If settlement occurs

embankment had a slope of +- 24-26º and

after installation, Armorflex merely adjusts

8 000m2 of Armorflex 180 was used to line

to the new contours.

and protect it.”

The water resistance, durability and

As seen here Armoglex can easily be applied around the rocks.

Armorflex can be supplied as loose

strength of Armorflex can be seen at

usually tied together with a polyrene rope,

blocks on pallets for manual installation,

Alberton/Natalspruit where an Armorflex

whereas 3.15mm diameter galvanized mild

or in preformed mats for mechanical

lining c o n s t r u c t e d 3 0 y e ar s ag o is

steel wire is used for manual installations.

inst alla tion. T he uni f or m blo ck s ar e

performing well.

In all applications a vertical bending radius

interlocked both mechanically and with

Factory-assembled, Armorflex mats are

of 0.5 metre is achievable.


APPLICATIONS

23

CHRYSO PRODUCTS IDEAL FOR PRECAST CONCRETE WIND TURBINEs T he use of precast concrete as a

and it produces epoxies for the moulds used

construction material for wind-turbine

to manufacture the blades.

p o w e r - g e n e r a ti o n t o w e r s is o n th e

Wind turbines must be able to perform

increase. As the towers reach new heights

in harsh environments and that is why

to support higher-powered, longer-bladed

durability is a vital requirement for the

turbines, the need for greater structural

concrete mixes.

strength to cope with the turbine weights and bending forces is also increasing.

“P l a s t i c s h r i n k a g e c r a c k i n g a n d settlement cracking can penetrate the

This calls for tower segments with

full depth of a slab/precast unit, requiring

larger cross-sectional diameters. Precast

expensive remedial measures and even

concrete is ideally suited for this application

greater cost should the slab/precast

as it can be produced with portable concrete

element have to be replaced. ChrysoFibres

batch plants on site. Precast concrete has

form a three dimensional bond with the

an added benefit of job creation, especially

concrete matrix and prevents early micro

in some isolated communities where the

cracks from widening into serious, slab

turbines are installed.

threatening cracks,” Correia adds.

Chryso’s Fluid Premia range of super-

I v or B o dding t on, a .b .e .’s p r o du c t

plasticers play a vital role in the manufacture

manager: Concrete Repair and General

of precast-concrete elements for turbine-

Construction, says another key wind-

tower construction. The molecules in its

turbine durability issue is ensuring that

Premia range are highly effective water

reinforcement is covered with sufficient

reducers, of fer workability retention

concrete. “With insuf ficient concrete

between 30 and 45 minutes, and achieve

cover, the reinforcement may corrode –

high early strengths. This allows for fast

causing spalling and structural failure.

construction and helps offset demanding

a.b.e. has two remedies for this: silocoat

fatigue loads.

and duracoat. Silocoat is a cementitious

“T he Chryso Fluid Premia range is ideal for maintaining consistency in the

coating equivalent to 180 mm of concrete,” Boddington explains.

manu f ac tur e o f r einf or ced concr e te components,” says Eddie Correia, Chryso GM: Technical Ser v ices. “It r educes sensi ti v i t y to changes in aggr ega te moisture or production batch tolerances.” The average concrete wind turbine tower comprises 18 precast 1,8m high segments with diameters ranging between 600mm and two metres. Chryso demoulding oils facilitate the easy stripping of wind-turbine moulds, reduce labour costs and preserve moulds. “Most importantly, the demoulding oils play a huge role in creating a defect-free surface finish with consistent colour. Moreover, they allow for casting immediately after oiling, unlike older demoulding oils which require a standing period,” Correia adds. Another member of the Chryso Southern Africa Group, a.b.e. Construction Chemicals, supplies an extensive range of adhesives to cater for specific strengths

An onshore wind turbine in which precast concrete was used for both foundations and tower segments.

PRECAST VOLUME 7 • ISSUE 1 • 2013


APPLICATIONS

25

LAFARGE’S CEM II AIMED AT PRECAST CONCRETE PRODUCERS L afarge South Africa phased out its

product under steam or heat curing. In

last CEM I cement pr oduct in 2009

addition, the general attributes of a quality

with the introduction of the innovative

cement formulated with siliceous fly ash

Rapidcem CEM II 52,5N. A first for South

are especially relevant to the manufacture

Africa, Lafarge’s CEM II Rapidcem cement

of precast concrete products. These are:

formulation was developed in consultation

• Enhanced concrete workability, making

with precast concrete and construction

professionals to meet the demanding

moulds

needs of the industry. The company now

• Reduced water demand for given slump,

offers the local market a complete range

improving the water-to-binder ratio and

of high-quality new-generation cements, all

increasing ultimate compressive strength

extended with siliceous fly ash.

• Better cohesion, producing castings

Precast-concrete products such as roof

it easier to place concrete in precast

with more unif orm proper ties and

tiles, pre-stressed railway sleepers, pipes

appearance

and culverts, have to be tightly controlled

• Lower heat of hydration, reducing the

for consistent quality and appearance,

and their raw material specifications

• Enhanced impermeability and a denser M

are correspondingly stringent. Lafarge

South Africa recognised that established

• Better response to heat or steam curing

risk of cracking more durable hardened concrete

C

Y

CM

CEM I users would be extremely cautious

due to the activation of the pozzolanic

abou t sw i tching to a new, mar kedl y

MY reaction in fly ash, giving higher early

different product. Consequently, Rapidcem

age strength gain as well as improved CY

was developed by the company’s Quality

late strength.

CMY

Department Southern Africa (QDSA) to

At the time of Rapidcem’s launch in

offer performance advantages in addition

2009, the South Africa’s environmental

to the consistent quality associated with

control legislation was not as advanced

Lafarge products.

as Europe’s. The lower carbon footprint

K

Rapidcem achieves a superior

of Rapidcem and the rest of the Lafarge

per formance in areas traditionally

c emen t pr o duc t r ange w as no t the

associated with CEM I products. It meets

key selling f eatur e. However, today,

and exceeds the precast industry’s high

the environmental merits of Lafarge’s

early strength requirements at 24 hours

innovative approach to cement design are

and 2 days, while performing equal to or

being appreciated.

better than any other CEM I 52,5 N or R

T he f ac t tha t Rapidcem’s mar ke t acceptance was achieved so successfully was well illustrated when Rail2Rail awarded a five-year cement contract to Lafarge for the production of a significant portion of the country’s concrete rail sleepers. After a demanding specialised testing programme and on-site trials, Rapidcem met the exacting German specifications and outperformed competition from CEM I products. A new manufacturer of prestressed railway sleepers, GPT, is also making use of Rapidcem. Lafarge South Africa endeavours to ensure the benefits of its technology are available to all its customers, both large

Rapidcem precast concrete rail sleepers.

and small.

PRECAST VOLUME 7 • ISSUE 1 • 2013


applications

27

Retaining walls offer varied form and function Kanonberg Lifestyle Estate consists of 31 hectares situated at the foothills of Cape Town’s Tygerberg, flanked by the exclusive Welgedacht Estate to the south and the Tygerberg Nature Reserve to the west. The 150 freehold stands in this estate range from 730 to 3 000 square metres, complemented by open spaces and walking trails. Excavated space for a new house had to be retained to prevent soil erosion. To avoid the wall from becoming too steep and exceeding height restrictions, main c on tr ac t or, D e c or t on, designe d the

A retaining wall at Kanonberg Lifestyle Estate.

walls for the top and the bottom of the property using Terraforce L12 rockface

blocks, plants were established to create

and demonstrates an ability to combine

segmental concrete retaining block (crb).

sof tness and tex ture between the

form with function, while also providing

The crb wall was designed with several

concrete blocks. Terraforce 4x4 Multi-

th e n e c e ssar y er o sion c on tr ol, an d

terraces to accommodate a small golf

Step blocks were incorporated to provide

maintaining good visual aesthetics that

green, outdoor patio, trampoline and

comfortable access to the different levels.

will continue to improve in tandem with

sandpit. At all levels and inside most

The wall was completed in April 2012

plant growth.


28

CMA members

Producer members company name

telephone

PROVINCE

telephone

PROVINCE

A Fick Sementwerke

(022) 913 1921

WC

PB

Kwena Brickforce

(00267) 392 2850

BOTS

PB/PI

Bass Beams

(031) 784 1920

KZN

PB

Lategan Cement

(021) 873 1154

WC

PB

Bay Brick

(035) 792 5218

KZN

PB

Marley Roofing

(011) 316 2121

JHB

PB

Beta Tiles

002634 2925303 002634 333422

ZIM

PB

Mobicast

(044) 874 2268

WC

PB/PI

Boland Concrete

(021) 875 5365

KC

PB

MVA Bricks

(012) 386 0050

JHB

PI

Bosun Brick Midrand

(011) 310 1176

JHB

PB

ReMacon

(011) 393 5504

JHB

PI

Brickcast

(031) 507 5525

KZN

PI

Revelstone

(0861) 173 835

WC

PB

0026 244 2107/8

BOTS

PB/PI

Reya Pele Bricks

(016) 363 0340

JHB

PB

C.E.L. Paving Products

(021) 905 5998

WC

PI

Rocla

(011) 670 7600

JHB

PB/PI

Cape Brick

(021) 511 2006

WC

PB

Salberg

(011) 357 7600

JHB

PB/PI

Cast Industries

(011) 316 2375

JHB

PB/PI

(041) 372 1933/372

EL

PB

Colonial Stone

(011) 794 9737

JHB

PB/PI

(011) 914 8500

JHB

PB/PI

Concrete Units

(021) 386 1923 (016) 3622236

WC/JHB

PB/PI

Style Decor

087 941 3889 071 744 2091

JHB

PB/PI

Conframat

(0861) 33 5599

JHB

PB/PI

Technicrete

(011) 674 6900

JHB

PB/PI

Corobrik

(031) 560 3111

KZN

PI

Topfloor

(021) 951 7700

WC

PB

Coverland/Monier

(011) 222 7300

JHB

PB

00263 04 746955

BOTS

PB/PI

Vanstone

(012) 541 2056

JHB

PI

Deranco Blocks

(041) 463 3338

EL

PB/PI West End Clay Bricks

(011) 851 1098

JHB

PI

Eagle Roof Tiles

(044) 874 0290

EL

PB

Echo Prestress

(011) 589 8800

JHB

PB

(00267) 71 321528

BOTS

PB

Inca Concrete Products

(021) 904 1620

WC

PB/PI

Inca Masonry (Garden Architecture)

(043) 745 1215

EL

PB/PI

Infraset

(011) 876 5100

JHB

PB/PI

Kavango Block & Brick

(021) 856 5213

NAM

PB/PI

082 850 3512 082 442 2082

JHB

PI

Brickbuild T/as Panda

Fastdeck

Keystone Walling

PRECAST VOLUME 7 • ISSUE 1 • 2013

company name

Shukuma Flooring Southern Pipe Contractors

Vaka Concrete

CONTRACTOR members company name

telephone

Decoroton Retaining System

(021) 875 5155

WC

Friction Retaining Structure

(011) 608 4321

JHB

Kalode Construction

(011) 781 3814

JHB

PYW Paving

(031) 903 1736

KZN

Roadstone Civil &Paving

(011) 683 7080

JHB

S A Paving

(011) 483 1350

JHB


CMA MEMBERS

29

Associate Members company name

telephone

ARQ Consulting Engineers

(012) 348 6668

JHB

ILIFA Africa Engineers

(016) 981 0591

JHB

JC Paving

(011) 431 0727 079 884 7986

JHB

Pipes

(012) 644 0043

JHB

Sekhukhune & Associates

(012) 993 4776

JHB

SNA Civils & Development

(012) 842 0000

JHB

Terraforce Pty Ltd

(021) 465 1907

WC

Young & Satharia Consulting Civil Eng

(031) 207 7252

KZN

non-producer members company name

telephone

Able Equipment

(044) 874 1876

EL

Ash Resources Pty Ltd

(011) 886 6200

JHB

Birkenmayer H Pty Ltd

(011) 970 3880

JHB

BASF Construction Chemicals

(011) 203 2400

JHB

Chryso Southern Africa

(011) 395 9700

JHB

Kaytech Consulting cc

(031) 717 2300

KZN

Kerneos Southern Africa

(011) 444 3090

JHB

00 31 113 562 460

NETH

Manitou SA Pty Ltd

(011) 975 7770

JHB

Mapei

(011) 552 8476

JHB

Pan Mixers SA Pty Ltd

(011) 397 3754

JHB

(0049) 7391 5050 148

GER

SIKA South Africa

(031) 792 6500

KZN

Soilab Pty Ltd

(021) 988 7410

WC

Smartstone Pty Ltd

(011) 310 1161

JHB

Technical Finishes

(021) 535 4455

WC

Techmatik SA

+48 483690811

POL

Kobra Moulds B.V.

Rampf Formen GmbH

cement members company name PPC Cement Pty Ltd (JHB H.O)

telephone (011) 386 9000

JHB

PRECAST VOLUME 7 • ISSUE 1 • 2013


PRECAST  

PRECAST is the official journal of the Concrete Manufacturers Association (CMA)

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